SI2457-D-FT Silicon Laboratories Inc, SI2457-D-FT Datasheet - Page 102

• Manufacturer Part Number: SI2457-D-FT
• Description: IC ISOMODEM SYSTEM-SIDE 24TSSOP
• Manufacturer: Silicon Laboratories Inc

Specifications of SI2457-D-FT

• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

AN93
5.7.7. U46–U48 (DTMF Dial Registers)
U46–U48 set the DTMF power level, DTMF “on” time, and DTMF “off” time, respectively (see Table 54). The DTMF
power levels are set in register U46 as a 16-bit value with the format 0x0HL0, where H is a hexadecimal number
(0–F) for the dBm level of the high-frequency DTMF tone, and L is a hexadecimal number (0–F) for the dBm level
of the low-frequency DTMF tone. The power level is specified in –1 dB units. The DTMF output level is 0 dBm for
each tone if U46 = 0x0000 and –15 dBm if U46 = 0x0FF0. The default power level is –9 dBm for the high tone and
–11 dBm for the low tone.
U47 and U48 set the DTMF “on” time (DTNT) and “off” time (DTFT) respectively as hexadecimal values in
milliseconds. The default value for both U47 and U48 is 100 ms, and the range of values is 0–1000 ms.
102
Register
Register
U3A
U3B
U3C
U3D
U3E
U3F
U37
U38
U39
U40
U42
U43
U45
U46
U47
U48
PDMT
Name
PDBT
Name
DTNT
DTPL
DTFT
PDIT
PD0
PD1
PD2
PD3
PD4
PD5
PD6
PD7
PD8
PD9
Number of pulses to dial 0.
Number of pulses to dial 1.
Number of pulses to dial 2.
Number of pulses to dial 3.
Number of pulses to dial 4.
Number of pulses to dial 5.
Number of pulses to dial 6.
Number of pulses to dial 7.
Number of pulses to dial 8.
Number of pulses to dial 9.
Pulse dial break time (ms units).
Pulse dial make time (ms units).
Pulse dial interdigit time (ms units).
DTMF power level
DTMF “on” time (ms units).
DTMF “off” time (ms units).
Table 54. DTMF Dial Registers
Table 53. Pulse Dial Registers
Rev. 1.3
Description
Description
Default
0x000A
0x003D
Default
0x09B0
0x0001
0x0002
0x0003
0x0004
0x0005
0x0006
0x0007
0x0008
0x0009
0x0027
0x0320
0x0064
0x0064